BOP TH400 - adapter plate and Hughes spacer
#1
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BOP TH400 - adapter plate and Hughes spacer
Thought I'd ask this in case anyone has tried this...
I have a BOP transmission from a 72 Firebird. I have the adapter plate to adapt an SBC to a BOP transmission:
That adapter plate measures 3.25mm in thickness.
I have the Hughes LS1 crank spacer:
Now the hub on my BOP torque converter looks shallower than an sbc torque converter hub.
Here's the sbc torque converter hub:
and here's the bop torque converter hub:
My question is has anyone tried mating a BOP TH400/TH350 and torque converter to an LS1 with the Hughes crank spacer and adapter plate?
I have a BOP transmission from a 72 Firebird. I have the adapter plate to adapt an SBC to a BOP transmission:
That adapter plate measures 3.25mm in thickness.
I have the Hughes LS1 crank spacer:
Now the hub on my BOP torque converter looks shallower than an sbc torque converter hub.
Here's the sbc torque converter hub:
and here's the bop torque converter hub:
My question is has anyone tried mating a BOP TH400/TH350 and torque converter to an LS1 with the Hughes crank spacer and adapter plate?
#2
Because you have two totally different covers on those converters it is hard to say if in fact the dimensions of the pilots are different. The best advise I can give you is to take and hold the one you plan on using up to your engine. See if the pilot goes into the crank especially on the red converter. The other issue you might face is with the bop adapter. This is going to change your converter spacing. I would just get the right case and forget about that adapter all together. Vince
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Vince, thanks for the response. The red converter I've already got installed in another car with a Chevy TH400 and the Hughes spacer (working great).
I'll test fit the black bop converter and see. I think you're right though, the bop converter hub will probably be a little short. If that's the case, and all the crank spacer does is have a spot for the converter hub to sit in, couldn't I potentially get a longer spacer? Or, is there a way to make that converter hub a little longer?
I'll test fit the black bop converter and see. I think you're right though, the bop converter hub will probably be a little short. If that's the case, and all the crank spacer does is have a spot for the converter hub to sit in, couldn't I potentially get a longer spacer? Or, is there a way to make that converter hub a little longer?
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Ok, apparently transmission shops can make that hub part longer somehow. I still don't know how they do it and make that stable - welding? burnishing?
I found this adapter also, it looks like it elongates the hub to fit in the back of an SBC crank:
http://www.jegs.com/i/Trans+Dapt/969/0055/10002/-1
So with the Hughes spacer, the 3.25mm thick adapter plate, and the Transdapt 0055 tc hub extender, this should work.
Anyone see a problem with this?
Thanks again for any help!
I found this adapter also, it looks like it elongates the hub to fit in the back of an SBC crank:
http://www.jegs.com/i/Trans+Dapt/969/0055/10002/-1
So with the Hughes spacer, the 3.25mm thick adapter plate, and the Transdapt 0055 tc hub extender, this should work.
Anyone see a problem with this?
Thanks again for any help!
#5
The two extrenders/spacers look to be the same thing. How much will the transdapt part extend the hub? You only need .525 total, with the adapter plate and the non-LS convertor.
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That's a good question...I'm not sure. All it says in the description is "Aligns converter with crank on Chevy/GM when using 5/16" engine plate."
On the Cadillac Power forum, this guy said with a .272" thick adapter plate, the TransDapt 0055 extender worked perfectly. My TCI adapter plate is 0.13" thick.
On the Cadillac Power forum, this guy said with a .272" thick adapter plate, the TransDapt 0055 extender worked perfectly. My TCI adapter plate is 0.13" thick.
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You're going to find that adapting a BOP trans to an LS1 is a huge pain in the ***, and it's going to be tough to live with spacers piled up on each other.
Torque converter shops would put that in a lathe, cut the crank pilot off and weld a longer one on, on the same machine they weld the pump drive tube and converter halves together.
I buy th400 cores for $40. I'd swap the case.
I've used the bop adapter with a gen 1 sbc.
It worked OK.
But you're looking at two problems.
1. trans won't bolt to engine without an adapter. An adapter that moves the already short converter further away.
2. torque converter won't seat in the crank without piling two adapters together.
Maybe it can be done. I'd go for the th400 chevy case, and the hughes adapter.
It almost looks like half the crank pilot of that bop converter is broken off.
I've seen the half stay in the crank and the converter get hauled off to be used. It's onlt held on with one big tack weld in the center.
As long as you pay attention to detail it might work.
Torque converter shops would put that in a lathe, cut the crank pilot off and weld a longer one on, on the same machine they weld the pump drive tube and converter halves together.
I buy th400 cores for $40. I'd swap the case.
I've used the bop adapter with a gen 1 sbc.
It worked OK.
But you're looking at two problems.
1. trans won't bolt to engine without an adapter. An adapter that moves the already short converter further away.
2. torque converter won't seat in the crank without piling two adapters together.
Maybe it can be done. I'd go for the th400 chevy case, and the hughes adapter.
It almost looks like half the crank pilot of that bop converter is broken off.
I've seen the half stay in the crank and the converter get hauled off to be used. It's onlt held on with one big tack weld in the center.
As long as you pay attention to detail it might work.